Vol. 5 Num 1002 Mon. March 26, 2007  
Front Page

FAQs on bird flu
1. What is Bird Flu?
Bird flu or avian influenza is an infectious disease of birds ranging from mild to severe form of illness. All birds are thought to be susceptible to bird flu, though some species are more resistant to infection than others. Some forms of bird flu can cause illness to humans.

2. What causes bird flu?
Bird flu is caused by different subtypes of influenza A virus affecting chickens, ducks and other birds Viruses which cause mild disease can mutate into viruses that can cause serious disease (highly pathogenic).

To date, all outbreaks of the highly pathogenic form have been caused by Influenza A /H5N1 virus, the only subtype that cause severe disease in humans.

3. How is bird flu transmitted in chickens and other birds?
Direct contact with discharges from infected birds, especially feces and respiratory secretions

Contaminated feed, water, cages equipment, vehicles and clothing

Clinically normal waterfowl and sea birds my introduce the virus into flocks

Eggs from infected hens can break and contaminate incubators

Birds that survive infection excrete virus for at least 10 days, orally and in feces. Highly pathogenic viruses can survive for long periods in tissue, water and the environment, especially when temperatures are low.

4. How do outbreaks of bird flu spread within the country?
1. Domestic birds can get the infection when they:

roam freely

share water supply with wild birds

use a water supply that might be contaminated by infected droppings

2. Contaminated equipment, vehicles, feeds, cages, or clothing, especially shoes can carry the virus from farm to farm

3. Wet markets where live chickens and other birds are sold under crowded and sometimes unsanitary conditions

5. How is bird flu transmitted to humans?
Bird flu is transmitted to humans from direct or indirect contact with infected wild ducks and chickens through infected aerosols, discharges and surfaces.

A person handling or taking care infected chickens or came near or inside a poultry or market where there are sick chickens can inhale the particles from dried discharges or feces with the bird flu virus.

Discharges can get in contact with the nose or eyes of a person handling infected chickens.

There is no reported case of bird flu in humans after handling dressed chicken. Since the virus is easily inactivated by heat, one does not get bird flu from thoroughly cooked chicken meat.

There is no evidence of human-to- human transmission.

6. Why are we concerned with bird flu?
There are a number of reasons why we are concerned with bird flu:

Bird flu or Avian influenza (AI) causes serious illness and death in humans

Avian and human influenza viruses can recombine to form a totally new influenza A virus which is capable of spreading from person to person and from which the human population do not have protection

AI causes severe epidemics and mass death of chickens affecting the poultry industry.

7. What are the signs and symptoms of bird flu in chickens?
Infection causes a wide spectrum of symptoms in birds, ranging from mild illness to a highly contagious and rapidly fatal disease resulting in severe epidemics.

Decrease in activity

Drastic decline in egg production

Facial swelling with swollen and bluish-violet colored combs and wattles

Hemorrhages on internal membrane surfaces

Virus isolation needed for definitive diagnosis

Gasping for breath




Sudden deaths (mortality that can reach 100%)

8. What are the signs and symptoms of bird flu in humans?
Bird flu is very similar to other influenza viruses. Initial symptoms are :


Muscle weakness and/or pain

Sore throat and cough

Sore eyes (conjunctivitis) is seen in some patients

Causes of death and complications are:

Severe viral pneumonia

Respiratory distress syndrome

Multi- organ failure

9. Since there are so many cases of influenza, pneumonia or any other respiratory illness, when does one suspect that the patient is a case of bird flu?
One suspects that a patient with influenza or pneumonia or any other respiratory illness is a case of bird flu avian influenza if the patient has had direct or indirect contact through handling or having taken care or getting near sick chickens or other birds.

A laboratory confirmation of the bird flu infection and epidemiologic link with unusual death or epidemics of chickens will support the diagnosis of bird flu.

10. What is the treatment of bird flu?
Treatment for H5N1 infection is essentially the same as for other influenza viruses. Antiviral drugs, some of which can be used for both treatment and prevention, are clinically effective against influenza A virus strains in otherwise healthy adults and children, but have some limitations. Some of these drugs are also expensive and supplies are limited.

11. Is there a vaccine against bird flu?
No. The vaccine currently available against the circulating strains in humans will not protect from the disease caused by H5N1. However, it is recommended for individuals who are potentially exposed to bird flu like poultry handlers, workers and breeders to prevent recombination of avian with the human influenza virus.

12. How do we prevent bird flu?
The ban on importation of live chickens and other poultry products from countries affected with bird flu is a critical step to prevent the entry of bird flu into the country.

For poultry caretakers and handlers of chickens and other birds:
Avoid contact of poultry with wild birds, in particular waterfowl

Control human traffic into poultries

Practice proper hand washing and cleaning and disinfection procedures in poultries

Report to authorities any unusual death or illness of chickens and other birds

Report to authorities any illness among the workers in poultry farms

For the general public:
Thoroughly wash hands with soap and water before and after handling chicken meat

Clean kitchen surfaces and utensils before and after use

Cook chicken well by seeing to it that the boiling temperature is reached

Do not sell live chickens in the market while there is a threat of bird flu.

Do not let chickens roam freely. Keep them in cages or pens.

Do not place chickens, ducks and pigs together in one area, cage or pen.

Do not catch, get near or keep in captivity wild birds.

Report to authorities any unusual death or illness of chickens and other birds

Report to authorities any case of respiratory illness with history of exposure to sick or dead chickens and other birds

13.What should Local Government Officials do?
Monitor and apprehend smuggling activities and illegal trading of poultry like game fowl, breeders and wild birds coming from countries affected by bird flu.

Pass and enforce local ordinances on the ff:

prohibition of live chickens in the market while there is a threat of bird flu

not allowing chickens to roam freely

prohibition of placing chickens, ducks and pigs together in one area, cages or pens

Provide correct information to the community.

Advise public not to catch, get near or keep in captivity wild birds

Coordinate with the local agricultural office for any unusual death or sickness of chicken and other fowl.

Coordinate with the nearest health worker for any suspected case of bird flu.

Coordinate with Department of Environmental and Natural Resources (DENR) on smuggling, trading or capture of wild birds by an individual.

14. Is it safe to travel to countries affected with bird flu?
Bird flu is not transmitted from one person to another. Individuals at risk are those are directly or indirectly exposed to sick chickens and other fowl. The government thereby advises travelers to countries affected with bird flu not to go to bird parks (aviaries), poultry farms or market where live poultry is sold.

Dr. Luningning P. Elio Villa
Medical Specialist IV and Program Manager
Emerging and Re-emerging Infectious Unit
National Center for Disease Prevention and Control
Department of Health